What is the resistance of an aluminum wire 1962.5 m long if its cross-sectional radius is 2.5 mm?

We calculate the resistance of the aluminum wire using the following formula:

R = ρ * l / S, where ρ is the resistivity of aluminum (at a temperature of 20 ºС ρ = 0.028 Ohm * mm2 / m), l is the length of the aluminum wire (l = 1962.5 m), S is the cross-sectional area of the wire (S = ΠR ^ 2, where R is the radius of the wire section (R = 2.5 mm)).

Let’s calculate the resistance of the wire:

R = ρ * l / ΠR ^ 2 = 0.028 * 1962.5 / (3.14 * 2.5 ^ 2) = 2.8 ohms.

Answer: The aluminum wire has a resistance of 2.8 ohms.